We want to mask (key_number - 1), not key_number. The current
implementation works fine for all values but the maximum one,
i.e. 8.

Signed-off-by: Samuel Ortiz <sameo@openedhand.com>
Acked-by: Eric Miao <eric.miao@marvell.com>
Signed-off-by: Dmitry Torokhov <dtor@mail.ru>

Signed-off-by: Eric Miao <eric.miao@marvell.com>
Signed-off-by: Dmitry Torokhov <dtor@mail.ru>

Currently, only one debounce_interval is introduced for both direct and
matrix keys. This is true in most cases, although the keypad controller
supports different debounce for direct/matrix keys.

Some platforms do require this to be tuned, instead of the default
reset value of 100ms.

Rotary encoder will always use zero debounce time for now to achieve
certain sensitivity.

Signed-off-by: Eric Miao <eric.miao@marvell.com>
Signed-off-by: Dmitry Torokhov <dtor@mail.ru>

1. use ioremap() for registers access, this improves the portability
   of the driver (e.g. same IP on different processor with different
   I/O memory range), and make it possible to remove those registers
   definition in pxa-regs.h as PXA is undergoing a clean-up of that
   header file

2. use device specific IRQ instead of hardcoded IRQ_KEYPAD, same
   reason as above

3. clean up the error handling path in _probe()

4. remove DRIVER_NAME and use pdev->name when necessary, we don't
   actually need a constant string literals

Signed-off-by: Eric Miao <eric.miao@marvell.com>
Signed-off-by: Dmitry Torokhov <dtor@mail.ru>

1. Rotary encoder events can be configured either as relative events
   as the legacy code does or as any specified key code, this is
   useful on some platform which uses the rotary keys as
   KEY_{UP/DOWN/LEFT/RIGHT}

2. Add support for direct keys, the corresponding keycodes for each
   direct key can now be specified within the platform data

3. Remove the direct/rotary key detection code from the IRQ handler
   to dedicated functions to improve readability

Signed-off-by: Eric Miao <eric.miao@marvell.com>
Signed-off-by: Dmitry Torokhov <dtor@mail.ru>

Introduce pxa27x_keypad_config() for keypad registers configuration
and remove the reg_kpc, reg_kprec from platform data structure
so that configurations of keypad registers can be centralized to a
single function.

It can also be re-used when resuming.

Signed-off-by: Eric Miao <eric.miao@marvell.com>
Signed-off-by: Dmitry Torokhov <dtor@mail.ru>

 1. Introduce the "struct pxa27x_keypad" structure for driver specific
    information, such as "struct clk", generated matrix key codes and
    so on

 2. Use KEY() macro to define matrix keys, instead of original 8x8 map
    this makes definition easier with keypad where keys are sparse

 3. Keep a generated array in "struct pxa27x_keypad" for fast lookup

 4. Separate the matrix scan into a dedicated function for readability
    and report only those keys whose state has been changed, instead
    of report all states

 5. Make use of KPAS to decide the faster path if only one key has been
    detected

Signed-off-by: Eric Miao <eric.miao@marvell.com>
Signed-off-by: Dmitry Torokhov <dtor@mail.ru>

The pin configurations will slowly be moved to the board specific code
at initialization thus to make the driver more generic.

Signed-off-by: Eric Miao <eric.miao@marvell.com>
Signed-off-by: Dmitry Torokhov <dtor@mail.ru>

The controller should really be called keypad, and also align
the naming of functions and structures to use "pxa27x_keypad"
as prefix, instead of "pxakbd".

Signed-off-by: Eric Miao <eric.miao@marvell.com>
Signed-off-by: Dmitry Torokhov <dtor@mail.ru>

Signed-off-by: Andre Haupt <andre@bitwigglers.org>
Signed-off-by: Dmitry Torokhov <dtor@mail.ru>